Wednesday’s Quake Raises Questions About Possible Bigger Ones To Come

PASADENA (CBS) — The 4.1 earthquake that struck Wednesday night occurred near the Whittier fault, which has produced major quakes in the past, leading some to ask if it was a precursor to something bigger.

The quake, centered in Yorba Linda, lasted only seconds.

“I actually didn’t even notice the small earthquake,” said Pasadena resident Mary Reitze.

It was revealed Thursday that the shaker occurred very close to the Whittier Fault, a fault that can produce a magnitude 7.0 earthquake.

“When we have these moderate size earthquakes there is about one in 20 chance of it being a foreshock,” said Caltech seismologist Dr. Egill Hauksson.

There is fear among some in the scientific community that a smaller quake, so close to the Whittier fault, could trigger a much larger earthquake, like the 1987 Whittier Narrows quake.

The 5.6 earthquake killed eight and caused hundreds of millions of dollars in damage.

But Caltech scientists said there were no smaller quakes leading up to the 1987 temblor.

“That just happened out of the blue. There was no precursor and that was actually quite a deep earthquake, down about 12 to 14 miles,” Dr. Hauksson said.

Over the years scientists have learned more about how the earth moves and adjusts, but still they say that predicting the “big one” is nearly impossible.

“We all wish we could, but we can’t do that,” Dr. Hauksson said.

But Southern Californians who we spoke with did not seem that concerned about Wednesday’s quake.

“I really just don’t feel that worried about, you know, stuff that big,” said Enrique Guerrero of Pasadena.

But exerts said that it is a good time to check and make sure you are ready in case the big one does hit.

“It makes me want to go out and kind of buy some bottles of water just in case, have some food handy,” said Pasadena resident Adam Coppola.

Experts said that as time passes, the chances of seeing a larger quake after a much smaller quake diminishes.